To protect against duplicated or counterfeited technical units, secure authentication of a unit as an original product may be requested by the customer, for example. A relatively new method which may be used for secure authentications is based on the use of so-called physical unclonable functions (PUFs).
United States Published Patent Application No. 2009/0083833 discusses how PUFs, including an additional PUF module for authentication, may be implemented in a variety of electronic devices such as FPGAs, RFIDs, and ASICs. U.S. Pat. No. 7,681,103 discusses reliable generation of a device-specific value, using PUFs.